The invention concerns an internal combustion engine with at least one combustion chamber enclosed by a cylinder, and a piston moving in the cylinder.
Generic internal combustion engines (piston engines) with carburetion or fuel injection are sufficiently well known. Internal combustion engines of this type usually have several cylinders, in which an axially moving piston encloses a combustion chamber, in which the combustion of a fuel-air mixture fed into the combustion chamber occurs.
A well-known problem of internal combustion engines of this type is the formation of carbonization residues of the fuel and motor oil fed to the engine. These residues are bituminous and, in part, highly complex mixtures of hydrocarbons, which are deposited and accumulate on valves, piston surfaces, intake ports, injection nozzles, and the upper surface of the combustion chamber. These carbonization residues may accumulate to such an extent, especially on intake valves, that they produce undesired changes in the fluid dynamics or closing behavior of the valve. Carbonization residues can also have extremely negative effects on other component surfaces of the combustion chamber, for example, the piston working surfaces. The problem of carbon deposits affects especially internal combustion engines with direct fuel injection.